高性能AlPO4-14分子筛膜的制备及气体分离性能

制备了高性能的AlPO₄-14分子筛膜. 首先通过控制反应溶胶中水和模板剂的含量制备了形貌均一的AlPO₄-14分子筛, 分子筛的尺寸为15~18 mm; 然后采用晶种法即在反应凝胶中加入分子筛作为晶种进一步调控分子筛的大小, 使得AlPO₄-14分子筛的尺寸从15~18 mm减小到2~3 mm, 得到形貌均一的纯相片状晶体, 同时有效缩短了制备时间; 最后以多孔管状莫来石为支撑体, 采用二次生长法制备AlPO₄-14分子筛膜. 考察了2种不同大小的晶种对膜形貌和性能的影响, 发现以大尺寸的分子筛(15~18 mm)作为晶种制备的分子筛膜的分离层存在较多缺陷, 而采用小尺寸的晶种(2~3 mm)制备的膜层较均一致密. AlPO₄-14分子筛膜经高温脱除模板剂后仍然保持着纯相的AlPO₄-14晶型, 表明二次生长法促进了AlPO₄-14晶体在膜层中的生长且使其具有更高的结晶度和热稳定性. 在25 ℃, 100 kPa下, AlPO₄-14分子筛膜对H₂/CH₄, CO₂/CH₄和H₂/CF₄的理想分离因子分别为28, 40和1047, 且H₂和CO₂的渗透速率分别为6.3×10 ^-7和9×10 ^-7 mol·(m ²·s·Pa) ^-1; 对等摩尔CO₂/CH₄混合气体的分离因子为81.5, 且CO₂的渗透速率为8.8×10 ^-7 mol·(m ²·s·Pa) ^-1.     

具有不同电荷和手性的Co(Ⅲ)配合物跨人红细胞膜的动力学研究

研究了4种不同电荷的Co(Ⅲ)金属配合物跨人红细胞膜的动力学,并测定了它们跨人红细胞膜的一级反应动力学速率常数,发现[Co(C₂O₄)₃]^3-的跨膜速率明显高于[Co(en)₃]³⁺,[Co(en)₂(C₂O₄)]⁺和[Co(en)(C₂O₄)₂]^-,后3种配合物的跨膜速率常数随正电荷的减少略有增加,跨膜机制为简单扩散.[Co(C₂O₄)₃]^3-的跨膜速率受阴离子通道抑制剂DIDS明显抑制,抑制率为51.95%,推测其跨膜机制为部分经阴离子通道协同简单扩散过膜.人红细胞摄入L-[Co(C₂O₄)₃]^3-的速率明显大于D-[Co(C₂O₄)₃]^3-,显示了一定的手性选择性.     

氯化三烷基苄基铵萃取铂(Ⅳ)、钯(Ⅱ)的热力学研究

季铵盐是萃取铂、钯的优良试剂,已广泛应用于铂族元素的分离^[1-3],季铵盐从盐酸体系中萃取铂、钯是按阴离子交换机理进行的^[4-5]。金属配阴离子按阴离子交换机理与有机阳离子生成缔合物。PtCl₆^2-的电荷密度比PdCl₄^2-的小,根据最小电荷密度原理,Pt(Ⅳ)应比Pd(Ⅱ)易被萃取。     

两个新颖的铜-二氮杂菲和钼(磷, 硒)杂多酸组成的有机-无机杂合化合物: 合成和晶体结构

水热法合成了两个新颖的有机-无机杂合化合物{[Cu(o-phen)(H₂O)]₃[Mo₅P₂O₂₃]}•4.5H₂O (1) 和{[Cu(o-phen)- (H₂O)]₂[Mo₅Se₂O₂₁]} (2) (o-phen＝1,10-phenanthroline). 通过红外光谱和单晶X射线衍射分析确定了它们的结构. 结构分析表明两个分子结构中的相邻[Mo₅P₂O₂₃]^6－或[Mo₅Se₂O₂₁]^4－阴离子均由两个桥式的[Cu(o-phen)(H₂O)]单元连接成分别为风车状和双侧桥联状一维聚合链, 化合物1的双金属链又通过若干链间氢键形成层状堆积结构. 讨论了钼杂多酸阴离子和第二种金属-配体亚单元阳离子之间的相互匹配关系.     

Lindqvist型钼酸盐修饰的碳纳米管二阶非线性光学性质的理论研究

利用密度泛函理论(DFT)方法研究了[Mo₆O₁₉]^2-修饰的单壁碳纳米管的非线性光学(NLO)性质. 结果表明, [Mo₆O₁₉]^2-修饰的单壁碳纳米管作为特殊的有机-无机杂化体系, 具有显著的二阶非线性光学响应. 通过调整[Mo₆O₁₉]^2-与纳米管之间的角度, 体系的稳定性显示出规律性的变化趋势, 且二阶NLO响应发生了变化. 对静场二阶极化率(β_vec)有主要贡献的电子跃迁特征表明, [Mo₆O₁₉]^2-与碳纳米管之间角度的改变影响了分子内的给受体特征. 当角度达到30°时, 化合物显示出最大的β_vec值, 此时杂多阴离子簇为电子受体, 而碳纳米管为电子给体. 此外, 在碳纳米管的端位连接电子给体(如氨基)可有效地增大β_vec值.     

新型柱-层结构的金属有机配位聚合物的合成与性质

利用5-磺基间苯二甲酸单钠盐（NaH₂L）和La(NO₃)₃在水热条件下成功合成了一种新型配位聚合物[La(L)(H₂O)₃]_n·nH₂O（1, CCDC: 1422966）,其结构和性质经IR, X-射线单晶衍射,元素分析,热重分析和FL表征。结果表明：La³⁺为九配位,呈三帽三棱柱配位构型。化合物1基于La³⁺和L^3-配体的两种拓扑非等价节点,呈现出五连接3D柱层状金属有机骨架结构,Schlafli符号为(4⁵, 6⁵)。化合物¹的荧光发射峰位于410 nm,归属于配体到金属的电荷转移。     

钨铈杂多酸及其盐的研究(Ⅰ)——离子交换法制备钨铈杂多酸

用离子交换法制备了三种迄今未见报导的钨铈杂多酸溶液。其阴离子组成分别为[CeW₈O₂₈]^4-、[CeW₁₀O₃₅]^6-和[CeW₁₂WO₄₂]^8-。其中12-钨铈杂多酸制得了稳定的固体,从而揭示了钨饰杂多化合物中一个新的系列--Ce-12W系列。对该固体酸进行了元素分析、红外光谱、电位滴定、X光衍射和差热、热重分析,并对其结构进行了初步探讨。     

稀土化合物配位场理论的研究——SO(3)-Dn群的变换

本文应用唐敖庆等人的配位场理论方法,分析SO(3)-D_n群的变换,引进了D_n群不可约表示特征M的概念,统一给出了[-1]^Γ、[-1]^γ因子,SC(3)-D_n群S_mГγⁱ系数,D_n群V系数,D_n群不可约表示[Г²]和(Г²),交换因子(-1)^Г、θ(Г_MГ_MГ_M')等.并得到求SO(3)-D_n群V系数的公式,直接沟通SO(3)-D_n群链.并应用SLJГγ稀土偶合方案对EuP₅O₁₄基态谱项⁷F能谱作了分析.     

二苯并噻吩及其氧化物与离子液体相互作用的理论研究

采用密度泛函理论方法比较了DBT/DBTO₂和[BMIM]⁺[PF₆]^-/[BMIM]⁺[BF₄]^-的相互作用。对最稳定的[BMIM]⁺[PF₆]^-、[BMIM]⁺[PF₆]^--DBT、[BMIM]⁺[PF₆]^--DBTO₂、[BMIM]⁺[BF₄]^-、[BMIM]⁺[BF₄]^--DBT、[BMIM]⁺[BF₄]^--DBTO₂进行了NBO和AIM分析。结果表明,DBT和[BMIM]⁺[PF₆]^-/[BMIM]⁺[BF₄]^-中的咪唑环彼此相互平行,NBO和AIM分析表明它们之间发生了π-π相互作用。H1'和H9'形成的F…H氢键有利于π-π堆积作用的形成。DBTO₂倾向于趋近C2-H2和甲基基团形成O…H相互作用;DBTO₂优先吸附在[BMIM]⁺[PF₆]^-/[BMIM]⁺[BF₄]^-。在模拟油中,[BMIM]⁺[PF₆]^-和[BMIM]⁺[BF₄]^-离子液体对DBTO₂的萃取能力大于DBT,其原因是可能是DBTO₂具有较大的极性和O…H与F…H的氢键作用。     

激光拉曼光谱研究NiMoP浸渍液活性组分的结构 Ⅱ.不同有机添加剂的影响

采用激光拉曼光谱（LRS）技术对添加有乙二醇和柠檬酸的NiMoP浸渍液和用该浸渍液制备的NiMoP/Al₂O₃催化剂进行了表征,研究了乙二醇和柠檬酸含量对NiMoP浸渍液及浸渍过程中活性相组成、结构的影响。结果表明,乙二醇使NiMoP(0.063)浸渍液中H_{x\[PMo11O39\]⁽7-x)- 或Hx\[PMo9O31\]⁽3-x)-及Hx\[PMo12O40\]⁽3-x)- 杂多阴离子结构转化成Hx\[P2Mo5O23\]⁽6-x)- 结构,而柠檬酸能保持NiMoP(0.063)浸渍液中Hx\[P2Mo5O23\]⁽6-x)-、Hx\[PMo11O39\]⁽7-x)- 或Hx\[PMo9O31\]⁽3-x)-及Hx\[PMo12O40\]⁽3-x)-杂多阴离子结构共存,但导致Hx\[P2Mo5O23\]⁽6-x)-含量降低,Hx\[PMo12O40\]⁽3-x)-含量升高。相对乙二醇而言,柠檬酸有机添加剂能够更有效地阻止浸渍过程中各杂多阴离子结构在载体氧化铝孔道中的分解。}     

High resolution two-dimensional electrophoresis and sodium dodecyl sulphate-polyacrylamide gel electrophoresis of cheese proteins after rapid solubilisation

The proteins of cheese are rapidly solubilised by heating to 95 degrees C in buffered 2% sodium dodecyl sulfate, 5% 2-mercaptoethanol. Electrophoretic analysis of the solubilised proteins by either one-dimensional sodium dodecyl sulphate-polyacrylamide gel electrophoresis or high resolution two-dimensional electrophoresis yields reproducible patterns characteristic of an individual cheese and its extent of ripening. The patterns reveal (i) the residual amounts of milk casein and whey proteins, and (ii) the appearance of casein degradation products, including pink-violet components as detected by Coomassie Blue staining.     

The simplified technique of high resolution two-dimensional polyacrylamide gel electrophoresis: biomedical applications in health and disease

The application of our simplified technique of high resolution two-dimensional polyacrylamide gel electrophoresis (2-D PAGE) to human body fluids is reviewed. Serum/plasma protein changes associated with alcohol abuse, familial dyslipoproteinemia ("fish-eye" disease), and myocardial infarction are demonstrated. High resolution 2-D PAGE of amniotic fluid, cerebrospinal fluid, urine, and saliva is shown with reference to the work of others, and the detection of pink-violet staining "lumicarmines" in sweat and tear fluid is reported for the first time. General aspects relating to the methodology are discussed. These include sample preparation, the choice of electrophoresis conditions (denaturing or nondenaturing) and detection method (Coomassie Brilliant Blue or silver), and the effects of native protein pretreatment with sodium dodecyl sulfate prior to silver staining or isoelectric focusing gel shrinkage in glycerol prior to second-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis.     

The effects of the addition of the polyelectrolyte, poly(ethyleneimine), on the adsorption of mixed surfactants of sodium dodecylsulfate and dodecyldimethylaminoacetate at the air-water interface

The effects of the addition of the polyelectrolyte, poly(ethyleneimine), PEI, on the adsorption of the mixed surfactants of sodium dodecylsulfate, SDS, and dodecyldimethylaminoacetate, dodecyl betaine, at the air-water interface have been investigated using neutron reflectivity and surface tension. In the absence of PEI the SDS and dodecyl betaine surfactants strongly interact and exhibit synergistic adsorption at the air-water interface. The addition of PEI, at pH 7 and 10, results in a significant modification of the surface partitioning of the SDS/dodecyl betaine mixture. The strong surface interaction at high pH (pH 7 and 10) between the PEI and SDS dominates the surface behavior. For solution compositions in the range 20/80-80/20 mol ratio dodecyl betaine/SDS at pH 7 the surface composition is strongly biased towards the SDS. At pH 10 a similar behavior is observed for a solution composition of 50/50 mol ratio dodecyl betaine/SDS. This strong partitioning in favor of the SDS at high pH is attributed to the strong ion-dipole attraction between the SDS sulfate and the PEI imine groups. At pH 3, where the electrostatic interactions between the surfactant and the PEI are dominant, the dodecyl betaine more effectively competes with the SDS for the interface, and the surface composition is much closer to the solution composition.     

Surfactant-sensitive polymeric membrane electrodes

The development and testing is described of surfactant-sensitive electrodes in which the active element is a plasticised polymeric membrane containing a dissolved complex of a cationic and anionic surfactant. Electrodes made with poly(vinyl chloride) membranes plasticised with 40–60% tricresyl phosphate and containing cetyl trimethylammonium dodecyl sulphate are reasonably satisfactory for determining sodium dodecyl sulphate activities below and above the critical micelle concentration. A new class of membrane electrodes has been introduced in which ion-exchange groups are chemically bound to the ends of the poly(vinyl chloride) chains either through the use of an amine as chain transfer agent during polymerisation or by using the SO₃^? radical-anion as polymerisation initiator. The resulting electrodes are specific to anionic or to cationic surfactants but selectivity between different surfactants of the same charge sign is not high. The electrode lifetimes in micellar solutions are much higher than those of previously described electrodes because the electroactive material cannot be lost by solubilisation.     

Effect of strong detergents and chaotropes on the detection of proteins in two-dimensional gels.

The solubilization of a particular protein is mandatory for its subsequent resolution and detection in two-dimensional gels. However, the extraction solutions, that are compatible with the first-dimensional separation step, such as urea and 3-[(3-cholamidopropyl)dimethylammonio]-1-propanesulfonate (CHAPS), do not solubilize all proteins in a sample. We studied the effect of various common, strong detergents and chaotropes, widely used as solubilizing agents, such as sodium dodecyl sulfate, lithium dodecyl sulfate and guanidine hydrochloride, on the solubilization of the total and membrane proteins of the bacterium Haemophilus influenzae. The proteins solubilized with each system were analyzed by two-dimensional electrophoresis and these of interest were identified by matrix assisted laser desorption/ionization-mass spectrometry (MALDI-MS). Use of sodium dodecyl sulfate, lithium dodecyl sulfate or guanidine hydrochloride for the solubilization of total proteins of the microorganism resulted in the detection of several additional spots, representing mainly outer membrane proteins, in comparison with those detected in the soluble protein fraction. Solubilization of the proteins of the cell envelope fraction with sodium dodecyl sulfate did not result in a more efficient protein detection when compared to the extraction with the urea/CHAPS system. When the dry immobilized pH gradient strips were rehydrated in a solution containing the proteins of the membrane fraction solubilized with sodium dodecyl sulfate or lithium dodecyl sulfate, a larger number of protein spots were detected in comparison with strips that were rehydrated in the urea/CHAPS solution. However, no improvement was observed in comparison with protein application in sample cups. The additional proteins detected with the use of strong detergents and chaotropes are in the majority difficult to solubilize and less hydrophobic proteins.     

Controlled self-assembly of hexa-peri-hexabenzocoronenes in solution

Disc-shaped hexa-peri-hexabenzocoronenes (HBCs) peripherally substituted by flexible dodecyl chains (molecule 1) or rigid polyphenylene dendrons (molecules 2a,b and 3) were efficiently synthesized. Steric hindrance arising from the substituents, from less hindered dodecyl to bulky dendrons, was utilized to program the self-assembly of the HBC cores in solution. The high tendency of the hexadodecyl-substituted HBC 1 to aggregate was determined by concentration and temperature-dependent (1)H NMR spectroscopic measurements and nonlinear least-squares analysis of the experimental data. The rigid dendrons in molecule2a suppress the pi--pi interactions of the HBC cores to a certain extent, and a slow (with respect to the NMR time scale) monomer--dimer equilibrium is observed. This unique equilibrium was further controlled by temperature, concentration, and solvent to afford discrete monomeric or dimeric species. Further structural modifications such as the replacement of dodecyl groups in 2a with hydrogen atoms resulted in a stable dimer structure in 2b due to diminished steric hindrance, as supported by quantum chemical calculations. "Moving" the dendron arms closer to the HBC core gives molecule 3, which exists only as a nonaggregated monomer. UV-vis absorption and fluorescence spectra of these discrete species revealed obvious differences in their electronic and optoelectronic properties which can be explained by the existence or absence of pi--pi interactions.     

Sodium dodecyl sulfate-polyacrylamide gel electrophoresis without a stacking gel: use for high sample throughput

Sodium dodecyl sulfate-polyacrylamide gel electrophoresis without a stacking gel minimizes lateral spreading of protein when samples are applied in agarose wells and allows high sample throughput (6 samples/cm gel width). The method is simple and convenient to use and gives comparable resolution to the standard method with 4-20% or 6-30% polyacrylamide gradient gels. Best results are obtained when the upper zone of the separating gel is of low polyacrylamide concentration. This indicates a need for the molten agarose to penetrate and anneal with the separating gel.     

Phase and extraction equilibria in H<Subscript>2</Subscript>O–sulfonol–HCl (H<Subscript>2</Subscript>SO<Subscript>4</Subscript>) and H<Subscript>2</Subscript>O–sodium dodecyl sulfate–HCl (H<Subscript>2</Subscript>SO<Subscript>4</Subscript>) systems

Solubility isotherms of water–sulfonol–hydrochloric (or sulfuric) acid and water–sodium dodecyl sulfate–hydrochloric acid systems at 75°C and a water–sodium dodecyl sulfate–sulfuric acid system at 50°C are constructed. Regions of two-phase liquid equilibrium suitable for use in extraction are found. Concentration parameters for extraction are determined. The interfacial distribution of a series of metal ions with and without such additional complexing reagents as diantipyrylmethane and diantipyrylheptane is studied.     

Solute-solvent interactions in micellar electrokinetic chromatography: V. Factors that produce peak splitting

The experimental conditions that produce analyte peak splitting in micellar electrokinetic capillary chromatography (MEKC) have been systematically investigated. The system studied was a neutral phosphate buffer and sodium dodecyl sulfate (SDS) micelles as pseudostationary phase. A number of analytes showing a wide variety of hydrophobicity values and several organic solvents as sample diluents have been tested. Peak splitting phenomena are mainly due to the presence of organic solvent in the sample solution. They increase with the hydrophobicity of the analyte and decrease with the increase of the surfactant concentration. When hydrophobic compounds are analyzed the suggested ways to avoid split peaks are: (i) the use of 1-propanol or 1-butanol as sample diluent instead of methanol or acetonitrile or (ii) the use of high concentration of surfactant in the separating solution when the analyte must be dissolved in pure methanol or acetonitrile.     

An environmentally friendly sodium dodecyl sulfate‐synergistic microwave‐assisted extraction followed by ultra‐high‐performance liquid chromatography with photodiode array method for the simultaneous extraction and determination of iridoids,phenylpropanoids, and lignans from Eucommiae Cortex

A simple and green sodium dodecyl sulfate‐synergistic microwave‐assisted extraction method was developed to extract and determine the iridoids, phenylpropanoids, and lignans in Eucommiae Cortex followed by ultra‐high‐performance liquid chromatography with photodiode array detection. The biodegradable solution (sodium dodecyl sulfate) was used as a promising alternative to organic solvents. The response surface methodology provided the optimum extraction conditions (2 mg/mL sodium dodecyl sulfate, 1100 W microwave power, and 6 min extraction time). The recoveries of three types of components ranged from 95.0 to 105% (RSDs < 5%). The intra‐ and inter‐day precision and accuracy were less than 3.40% and within the range of 97.1‐105%, respectively. Compared with other extraction methods, this newly established method was more efficient and environmental friendly. The results demonstrated that sodium dodecyl sulfate‐synergistic microwave‐assisted extraction followed by ultra‐high‐performance liquid chromatography with photodiode array method was applicable for the simultaneous extraction and determination of these three types of compounds for quality evaluation of Eucommiae Cortex.